Balance control?

Lewm and Slaw are correct. Using the placement of a vocalist in the mix is not reliable.
And if your problem is not electronic you could be obsessing over something that could have you chasing your tail for some time, instead of enjoying your records.

Here’s something that happened to me.
After upgrading my turntable table in 2020 I pulled out a test record I had picked up at a used record fair for $1. My main purpose was to check the anti-skating. But a couple of tracks also helped me to evaluate channel balance, which up to that point I thought was just fine. Turns out, it wasn’t, It was skewed noticeably to one side.

Even though my speakers are are equidistant from the side walls and the wall behind them my room layout is asymmetrical. I have CD racks on one side and records on the other and the location of doors, windows, electric outlets together with media storage dictated placement of everything that goes against a wall. I am convinced that this is what caused the sound to tilt a bit to one side.

The test record and the balance control on my preamp helped me to solve the problem. And when I did, it was like… aaaaahh.

Your preamp’s balance control will set you free.
As God and the manufacturer intended.
Peace and long life.

Woof

@woofman74 fair enough. Thanks for the input to you and everyone here. Much appreciated! 

Resurrection of an old thread, but I also run a Herron VTPH-2A phono stage. Keith was kind enough to include gain and trim pots for each channel to help with tube imbalance if this is indeed the case. There can be many causes, as per the posts above, but if you trace it back to the phono stage don't be afraid to try a little trim. 

@bimmerman2 wow really?! That’s very cool. Yeah Keith is a very helpful and pleasant guy to chat with. What are trim pots? Are they different from the loading plugs?

They are different from the loading plugs, which I don’t use with my Aphelion cartridge as per Keith’s suggestion. The pots are inside next to the tubes and are labeled, you just have to remove the top cover. You can turn them with a small screwdriver. On mine I ended up having to lower the louder channel a bit and increase the quieter one as the adjustment range isn’t huge. I’ll post a picture in my virtual systems section under "Final Set" so you can see them. They are the little blue pots. There are 3 per channel, gain, trim and bias. Don't mess with the bias pots.